Adaptimmune and GSK announced their strategic collaboration and license agreement in June 2014 for up to five programs including the first program, NY-ESO. The terms of the agreement were expanded in February 2016 to accelerate development of NY-ESO SPEAR T-cell therapy toward registration trials in synovial sarcoma, to explore development in myxoid/round cell liposarcoma (MRCLS), and to enable combination studies. In September 2017, GSK exercised its option to exclusively license the right to research, develop, and commercialize Adaptimmune's NY-ESO SPEAR T-cell therapy program.

Following the transition of the NY-ESO program, GSK has the right to nominate its third and fourth targets. GSK already nominated PRAME as its second target in January 2017. Adaptimmune will take these three additional targets when nominated, including PRAME, through preclinical testing to an IND‑ready state, at which point GSK will be responsible for IND filing. Adaptimmune will not be responsible for any clinical work on these additional programs.

On October 24, 2022, GSK notified Adaptimmune that they will transfer the NY-ESO cell therapy program and their rights to the PRAME program back to Adaptimmune. Timing and details regarding the transfer resulting from the termination of the agreement are still being negotiated.  Link to press release.